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Date: | Sat, 13 Aug 2011 01:08:59 +0000 |
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Meiosis begins with one DIPLOID cell containing two copies of each chromosome -- one from the organism's mother and one from its father -- and produces four HAPLOID cells containing one copy of each chromosome.
Each of the resulting chromosomes in the gamete cells is a unique mixture of maternal and paternal DNA, ensuring that offspring are genetically distinct from either parent. Gametes carry half the genetic information of an individual, 1n of each type.
In honey bees, the egg and sperm combine to produce females, which have normal diploid cells. The drone coming from the unfertilized egg, is stuck with only the mother's chromosomes and he is called haploid (since his cells have only 1 copy of each chromosome).
However, and this is the key point, in each egg the mother's chromosomes are a unique recombination of HER parents chromosomes. Hence, the genetic makeup of each drone will be different.
BUT, when the drone produces sperm, he cannot recombine both parents chromosomes, because he only got chromosomes from his mother, having come from an unfertilized egg. So, his sperm will all be identical, as we have said.
PLB
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